A fin module for a surfboard having a bore extending through the core between the top deck and the underside, including: a fin comprising a core and extending base portion, and a cover forming a fin blade made of resilient material; and a fin box having a cavity for receiving the base portion and adapted to receive an engagement end of a connector having a head anchorable at the top deck and an elongate member extendable through the core of the surfboard to pull the fin box toward the connector head.